Biotechnology and pharmaceutical companies are working on experimental vaccines to ward off the Epstein-Barr virus, with at least two development efforts in Massachusetts.
(NEW YORK) Ukraine claimed on Thursday that hundreds of people remain trapped in the Azovstal steel plant where the situation has become "desparate." Ukraine
Russia has launched its military offensive in the Donbas. Why has President Vladimir Putin refocused on eastern Ukraine, and what should we expect? NBC News takes a look.